Heretofore, a multitude of devices have been used for controlling the brain wave activity of a human subject. Certain of the prior art inventions produce the required effect through electrical or chemical stimulation of the nervous system. Others make use of flashing lights or sounds. While all such devices may be effective to a greater or lesser degree, they have certain drawbacks. For example, direct chemical or electrical nerve stimulation can have serious side effects such as temporary loss of memory, lethargy and the like. Flashing lights or sounds have been known to produce epileptic seizures in susceptible individuals and are at the very least distracting.
The alpha state characterized by a particular brain wave pattern, is manifested by a high degree of alertness found to be conducive to learning.
By way of prior art devices are the following U.S. Pat. Nos.: 3,219,028 to Giordino; 3,255,753 to Wing; 3,470,870 to Schoffer; 3,384,074 to Nautiola, et al; 3,712,292 to Zentmeyer; 3,718,132 to Holt, et al; 3,722,501 to Derouineau; 3,762,396 to Valentine, et al; 3,822,693 to King; 3,884,218 to Monroe; 3,967,616 to Ross; 3,993,043 to Adams, et al; 4,018,218 to Carlson, et al; 4,047,377 to Banks; 4,133,305 to Steuer; 4,157,088 to Gracey; 4,227,516 to Meland, et al; 4,282,864 to Pizer; 4,335,710 to Williamson; and 3,773,049 to Rabichev, et al.